A single coherent total ozone dataset, called the Multi Sensor Reanalysis (MSR), has been created from all available ozone column data measured by polar orbiting satellites in the near-ultraviolet Huggins band in the last thirty years.
Fourteen total ozone retrieval datasets from the satellite instruments TOMS, SBUV, GOME, SCIAMACHY, OMI, and GOME-2 have been used in the MSR. As first step a bias correction scheme is applied to all satellite observations, based on independent ground-based total ozone data
from the World Ozone and Ultraviolet Data Center. The correction is a function of solar zenith angle, viewing angle, time (trend), and effective ozone temperature. As second step data assimilation was applied to create a global dataset of total ozone analyses. The data
assimilation method is a sub-optimal implementation of the Kalman filter technique, and is based on a chemical transport model driven by ECMWF meteorological fields. The chemical transport model provides a detailed description of (stratospheric) transport and uses
parameterisations for gas-phase and ozone hole chemistry. The MSR dataset results from a 30-year data assimilation run with the 14 corrected satellite datasets as input, and is available on a grid of 1×1.5° with a sample frequency of 6 hour for the complete time
period (1978-2008).